TY - JOUR T1 - Effect of targeted therapy on circulating endothelial progenitor cells in precapillary pulmonary hypertension JF - European Respiratory Journal JO - Eur Respir J VL - 40 IS - Suppl 56 SP - P919 AU - Roberto Del Pozo AU - Jessica Garcia AU - Sandra Pizarro AU - Nuria Coll AU - Isabel Blanco AU - Yolanda Torralba AU - Víctor Peinado AU - Joan Albert Barbera Y1 - 2012/09/01 UR - http://erj.ersjournals.com/content/40/Suppl_56/P919.abstract N2 - Introduction: Endothelial dysfunction plays a key role in the development of pulmonary hypertension(PH).Bone marrow-derived endothelial progenitors cells (EPCs) may differentiate into functioning endothelial cells and contribute to endothelial repair.Aim:to investigate whether the number of circulating EPCs in patients with precapillary PH differs from control subjects and to assess the effects of targeted PH therapy on circulating EPCs.Methods: 36 control subjects (55±3 yrs) and 39 treatment naïve patients with precapillary PH (50±13 yrs;mean pulmonary arterial pressure,44±13 mmHg).33 patients had pulmonary arterial hypertension (PAH) (17 idiopathic; 16 associated);and 6 had chronic thromboembolic pulmonary hypertension (CTEPH).19 patients were re-evaluated at 6 months after the initiation of targeted PH therapy.The number of circulating EPCs was measured using flow cytometry.Circulating EPCs were defined as CD34+/CD133+ cells from a population that did not express CD45bright,and expressed as the percentage of lymphomonocytic cells.Results: In patients with precapillary PH,the number of circulating EPCs was lower than in control subjects[Md 0.060(0.037-0.075)and 0.086(0.063-0.120) % lymphomonocytes;p=0.001)] and was not correlated with functional class or hemodynamic measurements.After 6 months treatment,in patients with PAH(n=14)circulating EPCs increased[Md from 0.058(0.048-0.069) to 0.073(0.050-0.119)%;p=0.026],whereas in patients with CTEPH it did not.Conclusion: Patients with precapillary PH have reduced numbers of circulating EPCs that seems to increase as a result of targeted PH therapy.Supported by grants from SEPAR, SOCAP and GSK. ER -